9514 1404 393
Answer:
3rd box: -1 +14a +7h
Step-by-step explanation:
You will need to "simplify" the difference, then do the division by h.
f(a +h) = (6 -(a +h) +7(a +h)^2) = 6 -a -h +7(a^2 +2ah +h^2)
f(a +h) = 6 -a +7a^2 -h +14ah +7h^2
Then the difference is ...
f(a +h) -f(a) = 6 -a +7a^2 -h +14ah +7h^2 -(6 -a -7a^2)
f(a +h) -f(a) = -h +14ah +7h^2
Dividing this by h, we get ...
(f(a +h) -f(a))/h = (-h +14ah +7h^2)/h = -1 +14a +7h
